Investigators said a pilot at the Mason City Airport reported roads were icy and that he had encountered light ice when he flew into Mason City at about 6:30 p.m. on the same day as the crash.

Another witness who responded to the crash scene with the Ventura Fire Department said there was a coating of ice on his truck windshield that wipers would not clear. He also reported seeing a police car slide through an intersection on icy roads as it traveled to the crash scene.

Another witness reported weather conditions as “misty.” The NTSB report said the temperature was below freezing at -3 degrees Celsius, which is 26.6 degrees Farenheit.

The preliminary report lists witness accounts and information about weather conditions and the debris field after the crash. The investigation is ongoing and a final determination of what caused the crash has not been announced.